Picker stick linkage



Nov. 14, E950 G. H. HUFFERD PICKER STICK LINKAGE 2 Sheets-Sheet l FiledJuly 27, 1948 Y /ad /361 ,Ivrenfr l 650265 H. Huf-F620 Nov. 14, i950 G.H. HUFFERD PICKER STICK LINKAGE Filed July 27, 1948 2 Sheets-Sheet 2 l??y-Enbr 650265 /7C Huf/C590 Patented Novu 14, 1950 PICKER STICK LENKAGEGeorge H. Huiferd, Shaker Heights, Ohio, assignor to Houdaille-HersheyCorporation, Detroit, Mich., a corporation of Michigan Application July27, 1948, Serial No. 40,894

5 Claims.

This invention relates to an improved loom construction, andparticularly to an improved linkage for controlling the movements of thepicker stick of a ily shuttle type loom.

As is well known, the movement of the picker sticks of a loom is one ofthe most critical factors entering into the successful operation of theloom at high speed. In all loom constructions wherein a picker isrigidly secured to the top end of the picker stick, it is essential thatthe path of movement of the shuttle-engaging portions of the pickerdefine a substantially straight line, generally parallel to the path ofmovement of the shuttle along the lay.

In my copending application Serial No. 37,951, filed July 9, 1948, thereis described and claimed a unique control linkage for a picker stickembodying the supporting of the picker stick entirely from a primarybracket which is secured to the end of the rock shaft which is commonlyfound on all looms. The control linkage constituted a pair of linkswhich had their opposite ends respectively secured to spaced pivotbearings provided on the primary bracket vand on a secondary bracketwhich is adapted for rigid securement to the lower portion of the pickerstick. Specically, the construction of my above identied pendingapplication involved a lower link of substantial length which wasgenerally horizontally disposed and hence imparted primarily av lateralpositioning control upon the picker stick throughout the normal range ofmovement of the stick. The other link was relatively short in length andwas pivotally secured in depending relationship to a pivot bearing onthe primary bracket which was substantially laterally displaced from theend of the rock shaft. While such an arrangement has been found to bevery effective in controlling the movements of the picker stick `toprovide the required straight line path for the shuttle engagingportions of the picker, some difficulties were presented in obtainingthe necessary clearance for the various moving parts and particularly,in providing suicient space for the connection of a hydraulic check unitto operate between the primary and secondary brackets to check both theshuttle throwing and the shuttle catching movements of the picker stick.Furthermore, the essential geometry of the linkage involved symmetricaldisplacements of the short link on either side of its vertical position.

Accordingly, it is an object of this invention to provide an improvedcontrol linkage for the picker stick of a loom of the type employing apair of links pivotally connecting a picker stick Still another objectof this invention is the' provision of a double link support for apicker stick wherein both links pivot only through a very limited rangeto produce the requisite displacements of the picker stick andfurthermore wherein neither link passes a vertical position,

The specific nature of the invention, as well as other objects andadvantages thereof, will become apparent to those skilled in the artfrom the following detailed description of the annexed sheets ofdrawings, which, by way of preferred example only, illustrate twoembodiments of the invention.

On the drawings:

Figure 1 is a side elevational View of a picker stick control linkageembodying this invention, showing the linkage in assembled relationshipto the rock shaft and pickerstick of the loom.

Figure 2 is an end elevational view of the linkage of Fig.V 1 looking atsuch linkage from the rock shaft side thereof.

Figure 3 is a schematic View showing the various :positions assumed bythe linkage elements and the picker stick throughout the normal range ofmovement of the picker stick.

Figure 4 is a view similar to Fig. 3 but illustrating the movements ofthe picker stick accomplished by a modied form of the invention whereinlinks of non-uniform length are employed.

As shown on the drawings:

Referring to Fig. l, the numeral I0 indicates a rock shaft of a loom,while the numeral il indicates a conventional picker stick. The pickerstick Il is supported for oscillating movements with respect to the rockshaft l0, hence with respect to the lay of the loom (not shown), by alinkage constructed in accordance with this invention, which linkagecontrols the movement of the picker stick so that the shuttle-engagingportions of a picker (not shown) which is conventionally secured to thetop end of the picker stick, traverses a substantially horizontalstraight line path. In general, the linkage comprises a primary bracketI2, rigidly secured to the rock shaft I0, and a secondary bracket I3which is secured to the lower portion of the picker stick II andconnected to the primary bracket I2 by a pair of pivoted links I4 andI5. The links I4 and I5 may conveniently comprise either single ordouble links according to the nature of their pivotal support, but inthe particular example illustrated in the drawings, such links are bothdouble links, i. e., they each comprise a pair of identical parallellinks for reasons that will be more fully apparent later.

The primary bracket I2 constitutes an integral casting having a splitdepending portion [2a dening a cylindrical recess to receive the end ofrock shaft I0. The split portion I2a is clamped to the rock shaft III bya transverse bolt I2d and a transverse tapered key I1. The key I'I is oflongitudinally tapering configuration and is drawn into snug engagementwith the shaft I0 by a nut I8 threaded upon the threaded end portion ofthe key. As indicated in Fig. l, the surface of key I'l which contactsthe shaft III is of i concave conguration to provide a pair of parallelbiting edges Il@ to increase the securement of engagement of the primarybracket I2 with respect to the rock shaft I0.

In addition, primary bracket I2 delines a pair of vertically spacedpivot bearings I2b and I2c respectively. Both of such bearings aremounted in generally overlying relationship with respect to the end othe rock shaft IIJ and it should be particularly noted that the primarybracket I2 does not project laterally beyond the end of rock shaft II]to any appreciable extent. This arrangement greatly increases theclearance available for the various moving parts of the linkage.

The secondary bracket I3 may also conveniently comprise an integralcasting, being of generally U-shape configuration, and has the baseportion I3a rigidly secured to the front face of the picker stick II inany convenient manner. For example, a plurality of bolts I9 may be'provided which pass through a clamping plate engaging the rear face ofthe picker stick II and project through suitable holes in the secondarybracket base ISa to clamp the picker stick II between such space and theclamping plate 20.

Each of the arm portions I3b and I3c of the U-shaped secondary bracketI3 are of substantial height and hence project laterally from the pickerstick a substantial distance. At the outer end of each of the armportions, and respectively adjacent the top and bottom parts thereof, apair of bosses i3d and I3e are provided which respectively deiinevertically spaced pivot bearings I3f and I3g. As is best shown in Fig,2, the lateral spacing of the arm portions I3b and I3c of the secondarybracket I3 is suicient to permit such arm portions to straddle theprimary brackets I2 if necessary in one of the extreme positions of thepicker stick I I.

With the described arrangement, the upper pair of links I4 are pivotallysecured between the upper pivot bearings I2c and I3f while the lowerpair of links I5 are pivotally secured between the lower pivot bearingsI2b and I3g. The links I4 and I5 are each disposed outwardly of theprimary and secondary brackets I2 and I3 and are secured thereto bysuitable pivot pins I6.

With the described arrangement, and when the vertical spacing betweenthe primary bracket pivot bearings I2b and I2c is different from thevertical spacing of the pivot bearings I3f and I3g of the secondarybrackets, so that the upper links I5 and lower links I4 arenon-parallel, it will be found by ordinary design layout procedure, thatthe dimensions of the links I4 and I5 together with the spacing betweenthe various pivot bearings may be conveniently selected so as to insurethat the picker stick II will move along a path such that theshuttle-engaging portion of the picker stick will traverse asubstantially straight, horizontal line.

The embodiment shown 1n Figs. 1 and 2 of the drawings is particularlyadvantageous inasmuch as both the upper links I4 and the lower links I5are of identical size and hence interchangeable components may beemployed. Referring to the schematic diagram of Fig. 3, it is clearlyapparent that with the described linkage, the shuttle-engaging portionof the picker stick II, represented by the end of the short linedesignated IIa, will follow along a substantially horizontal straightline path when an oscillating movement is imparted to the picker stickII in conventional fashion, such as by the usual power lug (not shown).In this schematic diagram, the solid lines represent the intermediateposition of the picker stick II and the associated linkage, while thedotted lines and the dot dash lines represent the eXtreme positionsassumed by the picker stick.

The principles of this invention are not limited to arrangement whereinidentical links are employed for the upper and lower links I4 and I5. Asis clearly illustrated by the schematic diagram of Fig. 4, unequallength links may also be employed and by a suitable selection of thespacing between the various pivot bearings, this type of linkage willalso result in the shuttleengaging portions of the picker stick IImoving in a substantially straight line path. In the arrangement of Fig.4, the upper link I4 is shown as being of somewhat greater length thanthe lower link I5.

In both modications it should be noted that a relatively small range ofpivotal movement of the links I4 and I5 is required to produce the fullrange of movement of picker stick II. Furthermore neither link I4 or I5passes through a vertical position.

It should be particularly noted that due to the U-shaped configurationof the secondary bracket I3, and the location of the pivot bearings I3fand I3g in the ends of the arm portions of bracket I3, so that thepicker stick II is .located at a substantially laterally displacedposition with respect to the primary bracket I2, plus the fact that theprimary bracket I2 does not project laterally any substantial distancebeyond the end of the rockshaft I0, an unusually compact unit isachieved in which adequate clearance is provided between the variousmoving elements of the control linkage. This arrangement therefore ndsparticular utility in looms wherein it is desired to employ hydrauliccheck units for checking the shuttle throwing or shuttle catchingmovements of the picker stick. With the described arrangement, ahydraulic check unit may be conveniently mounted within the space denedbetween the arm portions I3b and I3c of the secondary bracket I3. Itwill be observed that such space is substantially free from interferencewith any of the components of the control linkage throughout the normalrange of movement of the picker stick II.

It will, of course, be understood that various details of constructionmay be modined through a wide range without departing from the principles of this invention and it is, therefore, not the purpose to limitthe patent granted hereon otherwise than necessitated by the scope ofthe appended claims.

I claim as my invention:

1. A linkage for controlling the movement of a picker stick oi a loomcomprising a primary bracket adapted for securement to the rock shaft ofthe loom, said primary bracket defining a pair of vertically spacedpivot bearings overlying the end of said rock shaft, a secondary bracketof generally U -shaped connguration having its base portion adapted forscour-ement to a picker stick and disposed with the portions thereofprojecting toward said primary bracket, said arm portions of saidsecondary bracket being suiiiciently laterally spaced to straddle saidprimary bracket, a rst pair of aligned pivot bearings respectivelyformed in the lower part of said arm portion, a second pair of alignedpivot bearings respectively formed in the upper part of said armportions, a pair of first links pivotally connected between the lowerpivot bearing of said primary bracket and said lower pivot bearings ofsaid secondary bracket, and a pair of second links pivotally connectedbetween the upper pivot bearing of said primary bracket and said upperpivot bearings of said secondary bracket, said pairs of links beingconstructed and arranged to control the movements oi s i" i stick toshift the shuttle-engaging portion thereof along a substantiallystraight line 2. A linkage for controlling the movement of a pickerstick of a loom comprising a primary bracket adapted for securement tothe rock shaft of the loom, said primary bracket dening a pair ofvertically spaced pivot bearings overlying the end of said rock shaft, asecondary bracket of generally U-shaped conguration having its baseportion adapted for securement to a picker stick and disposed with thearm portions thereof projecting toward said primary bracket, said armportions of said secondary bracket being sufiiciently laterally spacedto straddle said primary bracket, a nrst pair of aligned pivot bearingsrespectively formed in the lower part of said arm portion, a second pairof aligned pivot bearings respectively formed in the upper part of saidarm portions, a pair of links pivotally connected between the lowerpivot bearing of said primary bracket and said lower pivot bearings ofsaid secondary bracket, and an additional pair of links identical to therst mentioned pair of links pivotally connected between the upper pivotbearings of said primary bracket and said upper pivot bearings of saidsecondary bracket, said links and said pivot bearings being proportionedto control the movements of said picker stick to shift theshuttle-engaging portion thereof along a substantially straight linepath.

3. A parallel motion picker stick linkage for a shuttle loom comprisinga primary bracket defining a pair of generally vertically spaced pivotpoints, a `picker stick bracket arranged intermediate the primarybracket and a picker stick, said picker stick bracket defining a pair ofgenerally vertically spaced pivot points substantially laterallydisplaced from the picker stick, a rst link between the uppermost of thepivot points of said primary bracket and said picker stick bracket, saidfirst link being of a length less than the spacing dimension of thepivot points on said primary bracket, and a second link between thelowerrnost of the pivot points defined by said primary bracket and saidpicker stick bracket, said second link being of a length equal to thelength of said rst link, both of said links arranged to preclude pivotalmovement thereof through a vertical position.

1. A parallel motion picker stick linkage for a shuttle loom comprisinga primary bracket deiining a pair of generally vertically spaced pivotpoints, a picker stick bracket arranged intermediate the primary bracketand a picker stick, said picker stick bracket deiining a pair ofgenerally vertically spaced pivot points substantially laterallydisplaced from the picker stick, a first link between the uppermost ofthe pivot points of said primary bracket and said picker stick bracket,said first link being of a length less than the spacing dimension of thepivot points on said primary bracket, and a second link between thelowermost of the pivot points defined by said primary bracket and saidpicker stick bracket, said second link being of a length less than thelength of said rst link, both of said links arranged to preclude pivotalmovement thereof through a vertical position.

5. A parallel motion picker stick linkage for a shuttle loom comprisinga primary bracket defining a pair of generally vertically spaced pivotpoints, a picker stick bracket arranged intermediate the primary bracketand a picker stick, said picker stick bracket defining a pair ofgenerally vertically spaced pivot points substantially laterallydisplaced from the picker stick, a first link between the uppermost ofthe pivot points of said primary bracket and said picker stick bracket,said rst link being of a length less than the spacing dimension of thepivot points on said primary bracket, and a second link between thelowermost of the pivot points dened by said primary bracket and saidpicket stick bracket, said second link being of a length less than thespacing dimension of the pivot points dened by said picker stickbracket, both of said links arranged to preclude movement thereofthrough a vertical position.

GEORGE H. HUFFERD.

REFERENCES CITED The following references are of record in the iile ofthis patent:

UNITED STATES PATENTS Number Name Date 8,506 Perry Nov. 11, 1851 571,729Paige Nov. 17, 1896 FOREIGN PATENTS Number Country Date 605,104 GermanyNov. 5, 1934

